In-depth interview market research agency
FieldworkHub provides in-depth interview research and participant recruitment for online and in-person studies in the UK and internationally. We recruit carefully screened consumers, business professionals and specialist audiences to meet each project's specific criteria to support robust, reliable qualitative research.
1000+ IDI projects completed
IDIs run in 50+ countries
10k+ IDI participants recruited
Why in-depth interviews?
Why should you conduct IDI market research?
An in-depth interview, or IDI, is a one-to-one qualitative research interview in which a moderator explores a participant’s views, experiences and behaviour in detail. Unlike a focus group, the conversation is private and can be tailored closely to the individual respondent.
IDIs are particularly useful when the research topic is complex, sensitive or requires detailed exploration. They give moderators the flexibility to probe individual responses, follow unexpected lines of enquiry and understand the reasoning behind a participant’s attitudes or decisions.
In-depth interviews are widely used in consumer, B2B and specialist market research. They can be especially valuable when participants are senior, geographically dispersed, difficult to recruit, or unlikely to speak openly in a group setting.
IDIs can be conducted online, by telephone or face to face, depending on the audience and research objectives. They are suitable for everything from concept and product research to customer experience, professional decision-making and complex B2B studies.
The quality of an IDI study depends heavily on recruiting the right participants. FieldworkHub manages participant recruitment against detailed screening criteria, helping clients reach relevant consumer, B2B and specialist audiences.
IDI clients
Selected IDI market research clients
FieldworkHub has arranged in-depth interviews for some of the world’s leading brands...
Types of IDI
What are the different types of in-depth interview?
IDIs vary in terms of the amount of structure in the discussion guide.
Structured IDIs
Structured IDIs follow a predetermined set of questions, ensuring consistency across interviews and making responses easier to compare. The moderator works closely to a defined discussion guide, making this approach useful when specific information needs to be gathered from every participant.
They can be particularly effective in studies involving multiple markets or respondent types, where a consistent interview structure helps researchers compare findings across the sample.
Semi-structured IDIs
Semi-structured IDIs combine a core set of questions with the flexibility to explore topics in more depth as they arise. The moderator follows a discussion guide but can probe individual responses, pursue unexpected themes and adapt the conversation to each participant.
This balance makes semi-structured interviews particularly useful when researchers need consistency across interviews while still allowing room for richer qualitative insight.
Unstructured IDIs
Unstructured IDIs are more conversational and flexible, with no rigid sequence of predetermined questions. The moderator explores topics as they arise naturally, allowing the discussion to follow the participant’s experiences, priorities and perspective in greater depth.
This approach can be especially useful for exploratory research, where the objective is to uncover unexpected themes, understand complex experiences or generate new hypotheses.
Case studies
IDI case studies
FieldworkHub specialises in recruiting participants for in-depth interview research in the UK, Europe and international markets. We have recruited participants for more than 1,000 IDI projects across 50+ countries, including consumer, B2B, healthcare and specialist audiences.
Here is a selection of recent IDI recruitment and fieldwork projects.
Depth interviews: travel visa applicants, India, UAE
Our client was developing a new digital service to simplify the process of applying for international travel visas and wanted to conduct in- depth interviews with people who had recently applied for a UK visa and travel agency employees who assisted their customers with applications.
IDIs: 5 types of healthcare practitioners, USA
Our client wanted to interview five categories of healthcare practitioner in the USA (physicians, specialist gastroenterologists, pharmacists, nurses and hospitalists) on the topic of Clostridium difficile (C. diff), a type of bacteria that can cause severe diarrhoea and colitis.
IDIs: attitudes towards lab-grown diamonds, EU
A global mining group wanted to understand more about consumers’ attitudes towards diamond jewellery containing lab-grown rather than natural diamonds. FieldworkHub was asked to recruit four consumers in each of Germany, France, Italy and the UK who buy luxury goods. Respondents took part in remote IDIs.
IDIs: global social media behaviour
A client supporting a popular social media platform reached out to FieldworkHub to carry out IDIs with a sample of the platform’s users in Brazil, Egypt, Germany, India and Indonesia to discuss some features that were being developed to support discussions in the form of comments on posts.
Online IDIs: retailers on pop-up shops, UK
A leading retail landlord in the UK, was developing a new pop-up concept to encourage companies to experiment with temporary retail stores in the wake of the coronavirus pandemic. We arranged for direct-to-consumer retailers and traditional retailers to take part in online interviews over the course of two weeks.
Online IDIs: sustainability experts, 16 markets
We helped an NGO to complete a global climate sustainability study by arranging 42 online interviews across 16 markets with environment and sustainability experts from a variety of backgrounds. This successful project demonstrates our expertise in managing complex recruitment challenges across diverse markets.
Client testimonials
Testimonials from IDI clients
Here’s what some of our previous IDI clients say about us.
Working with the FieldworkHub team was truly a relief on a complex multi-country project. We used their local moderator and simultaneous translation services in a few markets. Winnie, as well as the local country teams, were adaptable, responsible and accommodating in a logistically challenging project. I value their partnership and will be tapping them in again on the next international project!
Kerry
Project Manager
Insights Agency
USA
FieldworkHub did an amazing job in setting up and managing one-on-one interviews for us. They were able to successfully recruit the people we needed, they did a fantastic job in setting up the interviews, and they showed outstanding attention to detail and precision in doing their job. I would strongly recommend choosing FieldworkHub as your research partner!
Simone
Research Manager
USA
Got questions?
Frequently Asked Questions
As consultants in the research space, we’ve got the answers to your questions about how to facilitate IDIs. And if there’s anything left unanswered, drop us an email or give the team a call. We’d be happy to help.
1
What kind of questions are asked in an in-depth interview?
Questions in an IDI or in-depth interview are usually open-ended and exploratory, designed to elicit detailed responses. They can cover a range of topics, including personal experiences, opinions, perceptions, and suggestions related to the research subject.
2
How long does an IDI typically take?
An IDI typically lasts between 30 to 90 minutes, depending on the complexity of the topic, type of profile, and the depth of information required.
3
How are participants chosen for IDIs?
Participants are typically selected based on specific criteria relevant to the research objectives, such as demographic factors, purchasing behaviour, or professional expertise, to ensure they represent the target audience.
4
How do IDIs compare to other qualitative methods like focus groups?
IDIs offer more depth and personal insight compared to focus groups, which may be influenced by group dynamics. IDIs allow for more private, candid responses, making them suitable for sensitive topics.
5
What is the typical cost of conducting IDIs?
The cost can vary widely depending on factors such as the type of respondent required, length of interview, the expertise of the interviewer, and whether the interviews are conducted in-person or remotely, but it’s generally more expensive to interview a given number of participants one at a time compared to running focus groups with the same number of people.
6
Can you recruit participants for B2B in-depth interviews?
Yes. We regularly recruit participants for B2B IDIs across a wide range of industries, functions and seniority levels. Recruitment can be targeted by criteria such as company size, sector, job title, seniority, purchasing responsibility and involvement in specific business decisions.
We can recruit for online, telephone and face-to-face interviews in the UK and international markets, including harder-to-reach professional audiences. All participants are screened against the agreed criteria to help ensure they are relevant, qualified and suitable for the research.
7
When should you use an IDI instead of a focus group?
IDIs are often the better choice when the subject is sensitive, the research requires detailed exploration of individual experiences, or participants are senior or highly specialised. Because the discussion is one-to-one, the moderator can probe each participant's responses in depth without the influence of other respondents.
Focus groups are generally more appropriate when interaction between participants is valuable and researchers want to explore how opinions develop through group discussion. The best approach depends on the research objectives, audience and subject matter.
Planning an in-depth interview research project?
Talk to our fieldwork specialists about participant recruitment and research support for online, telephone or face-to-face IDIs in the UK and international markets.
